Endoscope apparatus

ABSTRACT

An operational remote controller integrates a joystick for bending a bending portion of an inserted portion in an endoscope. A bending lever stands on the joystick. For every automatically returning of the bending lever to a neutral position, a CPU of the operational remote controller detects the neutral position and sets an insensitive band within a predetermined range of the neutral position. Thus, the insensitive band can be set within a relatively narrow range irrespective of variation of neutral positions. The CPU supplies positional information of the bending lever to a control circuit for controlling a motor drive circuit. The control circuit controls a motor drive circuit based on the supplied positional information, and the motor drive circuit drives a motor to bend the bending portion of the inserted portion.

This application claims benefit of Japanese Applications No. 2000-086993filed in Japan on Mar. 27, 2000, No. 2000-103858 filed in Japan on Apr.5, 2000, the contents of which are incorporated by this reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an endoscope apparatus suitable to benda bending portion provided for a tip of an inserted portion of anendoscope by using a joystick.

2. Prior Art Statement

Conventionally, an endoscope apparatus has been widely used. Theendoscope apparatus observes an examined site and performs variousprocessings by inserting a long inserted portion into a body cavity.Also, in an industrial field, an (industrial) endoscope apparatus hasbeen widely used. The (industrial) endoscope apparatus can observe andinspect an internal defect, corrosion, etc. of a boiler, turbine,engine, chemical plant, and the like.

The above-mentioned endoscope apparatus is structured such that abending portion capable of being manually operated is provided at abase-end side of a tip of the long inserted portion. The insertedportion has a CCD, etc. which is an image pickup means at the tip and acamera control unit (hereinafter, referred to as a CCU) at the side nearhand.

Image information obtained by using the CCD is transmitted to the CCU sothat a video signal is generated. An endoscope image can be displayed bysupplying the video signal to a display apparatus such as an LCD, a CRT,or the like.

Bending operation of the bending portion can be remotely operated by anoperational remote controller for endoscope (hereinafter, referred to asan operational remote controller). That is, the endoscope apparatus hastherein a motor for bending which can be controlled by the operationalremote controller. In the endoscope apparatus, a wire placed at thebending portion is towed and loosened by using a power of the motor,thereby enabling the bending portion to be remotely bent.

As the endoscope apparatus having the operational remote controller, anendoscope apparatus in which a joystick is provided as the operationalremote controller for bending operation is proposed as disclosed inJapanese Laid-open Patent Publication No. 10-328131. Incidentally, adetailed operating method of the joystick in the endoscope apparatus isnot disclosed in Japanese Laid-open Patent Publication No. 10-328131.

Also, for example, in an endoscope of European Patent ApplicationPublication No. 0543738A1, an endoscope apparatus in which anelectrically-driven bent inserted portion detachable from a processorcontrol module is operated by a joystick is proposed. This referencediscloses that, in the above-mentioned endoscope apparatus, theelectrically-driven bent inserted portion is positionally controlled bythe joystick. Further, the reference discloses that, in theabove-mentioned endoscope apparatus, a bent shape is electrically perked(locked against bending). Incidentally, European Patent ApplicationPublication No. 0543738A1 does not disclose a detailed operating methodof an operational button, etc. for positional control and lockingagainst bending in the endoscope apparatus.

The joysticks have variable resistors in which resistances are varieddepending on inclination angles of a lever. The joysticks can output ananalog voltage value in accordance with the inclination angles of thelever. As disclosed in European Patent Application Publication No.0543738A1, the joystick is frequently used for the positional control.

As the positional control using the above-described joystick, a methodfor proportioning the inclination angle of the lever to an offset of acontrolled target can be considered. For example, the positional controlusing the joystick has an advantage that an operator can easily grasp anactual angle of bending by proportioning the inclination angle of thelever (bending lever) to an inclination angle of the tip of the insertedportion.

However, when bending with an only fine angle, in the positional controlusing the joystick, the operational angle of the bending lever also mustbecome fine. Thus, the operator needs to concentrate his attention tohis fingertip and, therefore, fatigue from the operation is increased.

Then, in the endoscope-apparatus, a method (bending control at aconstant speed) in which an output of the joystick is handled as asignal indicating only a direction, not as an analog value correspondingto the inclination angle of the level, and the bending portion is bentin a pushed-down direction of the lever at a constant speed; is put intopractical use in order to solve the disadvantage of the positionalcontrol. Further, the endoscope apparatus, is sometimes employed, havinga function switching the positional control and the bending control atthe constant speed.

In the case of the bending control at the constant speed, the operatorcannot arbitrarily change a bending speed. Therefore, in the endoscopeapparatus using the bending control at the constant speed, the constantspeed is set to a slow speed, that is, driving in a slow mode isfrequent. When using the slow mode as the bending control at theconstant speed, the operability at the time of fine adjustment of thebending angle is excellent, however, the above endoscope apparatus has aproblem that it takes a long time until the inclination angle reaches adesired bending angle. In contrast, when using a fast speed as thebending control at the constant speed, the above endoscope apparatus hasa problem that the operability at the time of fine adjustment isremarkably reduced.

In the endoscope apparatus disclosed in European Patent ApplicationPublication No. 0543738A1, the bending locking of the bending portion ison by operating a bending lock switch which is laid out at a positiondifferent from that of the joystick for bending operation. Therefore, inthe endoscope apparatus, the bending locking cannot be performed byone-hand operation.

In the endoscope apparatuses, generally, it is impossible to confirmwhether or not the bending portion is locked and, therefore, it isconfirmed by employing light on/off of an LED, etc. near a switch.However, the operator must look aside from a monitor on which anendoscope image, etc. is displayed to confirm whether or not the bendingportion is locked by employing light on/off of the LED, etc., therebythe operability is inferior.

When the lever is not operated, the joystick is automatically returnednear a neutral position by energizing power of a spring. However, thereis a problem that the neutral position of the automatic returned leveris largely varied depending on precision of a spring or mechanism of thejoystick.

In the inventor's opinion, the periphery of the neutral position is setto an insensitive band taking account of the variation. When the leveris located at the neutral position, a method for stopping an output of apositional information signal can be considered.

However, the above-mentioned method has a problem that the leveroperation is not available within a predetermined range near the neutralposition and the bending operation is possible only by relativelylargely inclining the lever.

On the other hand, in a conventional endoscope apparatus for alwaystransmitting positional information without setting the insensitiveband, even if the lever is not operated, the positional information ofthe lever is outputted from the joystick. Therefore, the conventionalendoscope apparatus has a problem that processing efficiency of a CPU isreduced when using a controller for controlling by using the positionalinformation of the lever from the joystick.

For the above reasons, in the endoscope apparatuses, the precision ofoperability of the joystick cannot be increased.

Operational remote controllers with the above-mentioned joysticks havinga display for supplying a video signal which is signal-processed by theCCU to display the signal as an observed image are proposed as disclosedin, for example, Japanese Laid-open Patent Publication No. 10-328131 andU.S. Pat. No. 5,373,317.

The operational remote controller disclosed in Japanese Laid-open PatentPublication No. 10-328131 is structured such that a display and ajoystick is provided for a case having a predetermined volume. Since theabove operational remote controller has only the joystick for bendingoperation, it has a problem that operations other than the bendingcontrol cannot be executed.

In contrast, the operational remote controller disclosed in U.S. Pat.No. 5,373,317 is provided-with a display, a joystick, and key switchesfor various operations. The motor, and a signal processing control unitfor processing an image pickup signal from image pickup means areprovided in a case.

Since the above operational remote controller has the motor, signalprocessing control unit, and display, there is a problem that the outershape of the case is large, the weight is heavy, and various operationsare impossible while supporting the above operational remote controllerby one-handed grasping. Further, since the key switches are adjacent tothe display in the above operational remote controller, there is also aproblem that it is not user-friendly because the key switches areoperated only by positioning the hand aside from the joystick or only byoperation using the hand which grasps an inserted portion.

OBJECTS AND SUMMARY OF THE INVENTION

It is one object of the present invention to provide an endoscopeapparatus capable of improving bending operability using a joystick.

It is another object of the present invention to provide an endoscopeapparatus capable of improving the operational precision of bendingusing the joystick.

It is further another object of the present invention to provide anendoscope apparatus capable of user-friendlily performing operationnecessary for observation and inspection by one hand while performingbending operation with small size and light weight.

According to the present invention, an endoscope apparatus includes:bending drive means for bending a bending portion provided to a tip ofan inserted portion; an operating unit for bending and operating thebending portion by inclining a lever; and control means for allowing thebending drive means to bend and operate the bending portion based oninformation from the operating unit, for detecting the neutral positionfor every automatically returning of the lever to the neutral position,and for setting a predetermined range from the detected neutral positionto an insensitive band to prohibit bending driving of the bendingportion by the bending drive means.

According to the present invention, an endoscope apparatus includes:bending drive means for bending a bending portion provided for a tip ofan inserted portion; a bending operating unit for bending the bendingportion by inclining a lever; and a plurality of operating units, whichare provided for remotely controlling the endoscope apparatus, otherthan said bending operating unit and are provided distributively on thefront surface and a back surface of a case of an operational remotecontroller for endoscope.

The above and many other objects, features, and advantages of thisinvention will become apparent from the ensuing detailed description ofone preferred embodiment, which should be read in conjunction with theaccompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is an explanatory view of the overall endoscope system includingan endoscope apparatus according to a first embodiment of the presentinvention;

FIG. 2 is a block diagram showing the constitution of circuits in theendoscope apparatus;

FIG. 3 is an explanatory view for explaining an operating range of ajoystick;

FIG. 4 is an explanatory view for explaining operation according to thefirst embodiment;

FIG. 5 is an explanatory view showing the overall of an endoscope systemincluding an endoscope apparatus according to a second embodiment;

FIG. 6 is an explanatory view schematically showing the constitution ofa joystick in an operational remote controller in FIG. 5;

FIG. 7 is a flowchart for explaining operation in FIG. 7;

FIG. 8 is a flowchart showing an operational flow used in a thirdembodiment of the present invention;

FIG. 9 is a block diagram showing a fourth embodiment of the presentinvention;

FIG. 10 is a diagram showing the overall constitution of an endoscopeapparatus according to a fifth embodiment of the present invention;

FIG. 11 is an explanatory view of the structure of a drum in FIG. 10;

FIG. 12 is an explanatory view showing the structure of a motor drive inFIG. 11;

FIG. 13 is a front view showing an operational remote controlleraccording to a fifth embodiment of the present invention;

FIG. 14 is a back view showing the operational remote controller;

FIG. 15 is a side view showing the operational remote controller;

FIG. 16 is an upper end view showing an upper end of the operationalremote controller;

FIG. 17 is a lower end view showing a lower end of the operationalremote controller;

FIG. 18 is a cross-sectional view showing the operational remotecontroller;

FIG. 19 is explanatory views showing various structures of a bendinglever;

FIG. 20 is a constitutional cross-sectional view showing theconstitution of a slide switch of the operational remote controller;

FIG. 21 is an explanatory view showing the structure of a microphone ofthe operational remote controller;

FIG. 22 is an explanatory view showing a relationship between aconnector for LCD and a cable in the operational remote controller;

FIG. 23 is a block diagram showing a relationship between theoperational remote controller and an endoscope main body;

FIG. 24 is a side view showing an operational remote controlleraccording to a sixth embodiment of the present invention;

FIG. 25 is a cross-sectional view showing one part of the operationalremote controller in FIG. 24;

FIG. 26 is a lower end view showing a lower end of the operationalremote controller; and

FIG. 27 is an upper end view showing an upper end of the operationalremote controller.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIGS. 1 to 4 relate to first to fourth embodiments of the presentinvention in which FIG. 1 is an explanatory view showing the overall ofan endoscope system including an endoscope apparatus according to thefirst embodiment; FIG. 2 is a block diagram showing the constitution ofcircuits in the endoscope apparatus; FIG. 3 is an explanatory view forexplaining an operating range of a joystick; and FIG. 4 is anexplanatory view for operation according to the first embodiment.

In the present embodiment, operational precision is improved bynarrowing an insensitive range of a neutral position where an anglesignal from a joystick should be stopped.

An endoscope control unit 1 includes an accommodating unit 4 foraccommodating an endoscope 3 having a long inserted portion 2. Theinserted portion 2 of the endoscope 3 has a bending portion 5 b providedat a base-end side of a hard end portion 5 a and is bendable. Theendoscope control unit 1 comprises a CCU 6; a control circuit 7; and amotor drive circuit 8. The control circuit 7 controls each section ofthe endoscope control unit 1.

A CCD 10 (refer to FIG. 2) is provided for the end portion 5 a of theendoscope 3. The CCD 10 photoelectrically converts an optical image ofan object to be photographed, and outputs the converted signal to thecamera control unit (hereinafter, referred to as the CCU) 6. The CCU 6is controlled by the control circuit 7, thereby converting an inputsignal into a standard video signal for displaying it on a monitor.

The video signal from the CCU 16 is supplied to a monitor 9 via a cable.The monitor 9 displays an endoscope image onto a displayed screen basedon the input video signal.

A general PC 16 and the control circuit 7 are connected via apredetermined interface cable 16 b such as an RS232C or a USB. Thegeneral PC 16 incoporates image processing software. The endoscopecontrol unit 1 can perform predetermined image processing for theendoscope image displayed on the monitor 9 via the control circuit 7 byoperating the general PC 16.

As shown in FIG. 2, a plurality of wires for traction 28 are placed tothe inserted portion 2. One end of each wire for traction 28 is fixed ata predetermined position of the inserted portion 2. In the endoscope 3,each wire for traction 28 is properly towed, thereby bending the bendingportion 5 b of the inserted portion 2. Each wire for traction 28 istowed by a plurality of motors 27. Each motor 27 is driven by a motordrive circuit 8, thereby towing the wires for traction 28. The motordrive circuit 8 is controlled by the control circuit 7, therebycontrolling the driving of the motors 27.

In the present embodiment, an operational remote controller forendoscope (hereinafter, referred to as an operational remote controller)11 integrating a joystick 12 is used as remote control means for bendingoperation. A bending lever 13 of the joystick 12 capable of beinginclined vertically and horizontally by operator's operation stands onan upper surface of the operational remote controller 11. When theoperator performs no operation through the lever, the bending lever 13is automatically returned near a predetermined neutral position by anenergizing force of a spring (not shown).

As shown in FIG. 2, the joystick 12 has: a variable resistor 18 in whicha resistance changes corresponding to inclination in a horizontaldirection of the bending lever 13; and a variable resistor 19 in which aresistance changes corresponding to inclination in a vertical directionof the bending lever 13. The variable resistor 18 outputs a J/SR/Lsignal having a level corresponding to an inclination angle in thehorizontal direction of the bending lever 13. The variable resistor 19outputs a J/SU/D signal having a level corresponding to an inclinationangle in the vertical direction of the bending lever 13.

Outputs from the variable resistors 18 and 19 are supplied to a CPU 14of a remote control circuit 21 incorporated in the operational remotecontroller 11. The CPU 14 comprises A/D converters (A/Ds) 22 and 23. TheA/Ds 22 and 23 convert the J/SR/L signal and the J/SU/D signal intodigital signals and the CPU 14 fetches the converted signals.

The CPU 14 outputs the fetched J/SR/L signal and J/SU/D signal aspositional information. In the example shown in FIG. 1, the operationalremote controller 11 and control circuit 7 are connected by a remotecontroller cable 15 compliant with an RS232C standard, etc. The remotecontrol circuit 21 outputs the positional information to the controlcircuit 7 via an RS232C driver 25.

In the present embodiment, the CPU 14 determines whether or not thebending lever 13 automatically returns to the neutral position bymonitoring the J/SR/L signal and J/SU/D signal. When the CPU 14determines that the bending lever 13 returns to the neutral position,the J/SR/L signal and J/SU/D signal in this case are stored in a memory24 as the positional information at the neutral position.

Further, the CPU 14 sets an insensitive band within a predeterminedrange from the neutral position, as center, stored in the memory 24. Ifthe CPU 14 determines based on the J/SR/L signal and J/SU/D signal thatthe inclination of the bending lever 13 is within the range of theinsensitive band, transmission of the positional information to thecontrol circuit 7 is stopped.

The positional information is supplied via the remote controller cable15 and, based on the supplied positional information, the controlcircuit 7 controls the motor drive circuit 8, thereby bending thebending portion 5 b with a bending angle based on the positionalinformation.

Next, operation according to the embodiment with the above constitutionwill be described referring to FIGS. 3 and 4.

Assume that the operator bends the bending portion 5 b of the endoscopeinserted portion 2. The operator bends the bending portion 5 b by usingthe bending lever 13 standing onto the operational remote controller 11.More specifically, the operator inclines the bending lever 13 in adirection corresponding to a direction in which the bending portion 5 bis to be bent and inclines this inclination angle in accordance with theangle of bending.

The resistances of the variable resistors 18 and 19 in the joystick 12change by the inclining operation of the bending lever 13, and theJ/SR/L signal and J/SU/D signal with a level corresponding to theinclination angle are supplied to the CPU 14 of the remote controlcircuit 21. The CPU 14 fetches these signals by using the A/Ds 22 and 23and outputs them as the positional information.

The positional information from the remote control circuit 21 issupplied to the control circuit 7 in the endoscope control unit 1 viathe remote controller cable 15. The control circuit 7 controls the motordrive circuit 8 based on the positional information. Thus, the motordrive circuit 8 drives the motor 27 based on the positional information,thereby properly towing the wires 28 for traction. As a consequence, thebending portion 5 b of the inserted portion 2 is bent in a direction andwith an angle corresponding to the positional information.

Herein, assume that the operator does not touch the bending lever 13 ofthe joystick 12. Then, the inclination angle formed by the bending lever13 of the joystick 12 changes to the periphery of the neutral positionshown in FIG. 3 by an energizing force of a spring (not shown). In thiscase, the bending lever 13 is automatically returned to any positionwithin varied range corresponding to the variation of the spring, etc.Incidentally, as shown in FIG. 3, an ideal neutral position of thebending lever 13 is the center within the overall operation (range of amaximum inclination angle formed by the bending lever 13) and theautomatically-returned position is within a range of a predeterminedvariation around the neutral position.

When it is detected based on the output of the joystick 12 that thebending lever 13 returns to the automatically-returned position, the CPU14 stores the positional information in this case in the memory 24. TheCPU 14 sets an insensitive band within a predetermined range around thestored positional information. The CPU 14 determines whether or notvoltages of the variable resistors 18 and 19 change for several seconds,thereby detecting whether or not the bending lever 13 returns to theautomatically-returned position.

In the present invention, the returned positional information is storedin the remote control circuit 21 every automatic return and theinsensitive band is set within a predetermined range from the storedposition as center. For example, if the returned position is anA-position in FIG. 4, the CPU 14 sets an A-insensitive band shown by acurved arrow with the A-position as center. Also, for example, if thereturned position is a B-position in FIG. 4, the CPU 14 sets aB-insensitive band shown by a curved arrow with the B-position ascenter.

The CPU 14 determines whether or not the inclination of the bendinglever 13 is within the insensitive range based on the returned positionstored in the memory 24 by monitoring the J/SR/L signal and J/SU/Dsignal from the joystick 12. If it is determined that the inclination ofthe bending lever 13 is within the insensitive range, the CPU 14 stopsthe transmission of the positional information to the control circuit 7.

Now assume that the operator does not touch the bending lever 13 afterthe bending lever 13 is automatically returned. In this case, theinclination of the bending lever 13 is within the range of theinsensitive band. Therefore, no positional information is transmitted tothe control circuit 7 from the remote control circuit 21. Since thecontrol circuit 7 does not receive the positional information, thecontrol operation is not performed in the control circuit 7 based on thepositional information.

Herein, assume that the operator operates the bending lever 13 to bendthe bending portion 5 b. In this case, the operator inclines the bendinglever 13 to exceed the set insensitive band. Then, the CPU 14 detectsbased on the received J/SR/L signal and the J/SU/D signal that thebending lever 13 inclines out of the range of the insensitive band, andthe CPU 14 restarts the transmission of the positional information basedon the J/SR/L signal and the J/SU/D signal. In this case, differentlyfrom the conventional art, the CPU 14 does not set the wide insensitiveband which takes the variation of the spring, etc. into account.Therefore, the operator can instruct the bending by the operationthrough the lever with a relatively small inclination angle.

As a consequence, the control circuit 7 restarts receiving thepositional information and restarts the controlling an operation basedon the positional information obtained by the control of the motor drivecircuit 8, etc.

As mentioned above, in the present embodiment, when the operator doesnot operate the bending lever 13 of the joystick 12, the control circuit7 does not need to control with the bending operation. Therefore, thecontrol circuit 7 can execute other processes such as communication withthe general PC 16 and image processing during a time for processing thepositional information.

In addition, differently from the case of setting the wide insensitiveband in consideration of the variation of the spring, etc. as theconventional art, the CPU 14 can narrow the range of the insensitiveband. Consequently, the operator can instruct the bending by theoperation through the lever with a fine inclination angle, therebyobtaining the operability with high precision.

The CPU 14 resets the neutral position and the insensitive band by usingthe positional information every automatic return. Therefore, thebending lever 13 of the joystick 12 can be used within the range of thenarrow insensitive band even if the variation of the spring, etc. iswide. In the present embodiment, the operational remote controller forbending the bending portion 5 b can use an inexpensive joystick with lowprecision for the neutral position such that the automatically-returnedpositions are widely varied, thereby reducing costs.

If the bending lever 13 is within the range of the insensitive band, theCPU 14 does not transmit positional information from the joystick 12and, thus, the CPU 14 can stop the transmission and the processingcircuit. In other words, in the present embodiment, a consumed powerduring an inoperative time of the joystick 12 can be reduced.

Incidentally, in the above embodiment, after converting the analogsignal based on the operation of the joystick into the positionalinformation, the operational remote controller outputs the positionalinformation to the control circuit. However, the function for conversioninto the positional information, etc. may be provided at the endoscopecontrol unit. More specifically, the remote control circuit 21 may beprovided at the endoscope control unit and the analog signal from thejoystick may be transmitted to the remote control circuit. In this case,an apparatus using an existing joystick can be constituted.

FIGS. 5 to 7 relate to the second embodiment of the present invention inwhich FIG. 5 is an explanatory view showing the overall endoscope systemincluding an endoscope apparatus according to the second embodiment;FIG. 6 is an explanatory view schematically showing the constitution ofthe joystick in an operational remote controller in FIG. 5; and FIG. 7is a flowchart for explaining operation. Referring to FIG. 5, the samereference numerals as those in FIG. 1 denote the same components in FIG.1 and the description is omitted.

In the present embodiment, differently from the first embodiment, inplace of the endoscope control unit 1, an endoscope control unit 45 isemployed and, in place of the operational remote controller 11, anoperational remote controller 41 is employed.

The endoscope control unit 45 differs from the endoscope control unit 1in that a control circuit 43 and a motor drive circuit 44 are employed,in place of the control circuit 7 and the motor drive circuit 8,respectively. Also, the operational remote controller 41 differs fromthe operational remote controller 11 in that a joystick 31 and a CPU 42are employed, in place of the joystick 12 and the CPU 14, respectively.

FIG. 6 shows the cross-sectional view of the joystick 31. The bendinglever 13 is implanted to a spherical portion 34 rotatable in the up anddown and right and left directions and is provided to be exposed from anupper surface 33 of a case of the operational remote controller 41. Thejoystick 31 comprises: a variable resistor (refer to FIG. 2) in which aresistance changes corresponding to inclination of the bending lever 13in the right and left direction and a variable resistor in which aresistance changes corresponding to inclination of the bending lever 13in the up and down direction. The joystick 31 outputs an analog signalwith a level corresponding to inclination angles in the up and down andright and left directions of the bending lever 13 to the CPU 42. Thebending lever 13 is energized to be automatically returned to a neutralposition by a spring, etc. (not shown).

In the present embodiment, a tactile switch 35 is provided at the lowerside of the spherical portion 34 in the joystick 31. The sphericalportion 34 is not only rotatable in the up and down and right and leftdirections but also can be moved in an axial direction of the bendinglever 13 by lowering the bending lever 13 in the axial direction.

The spherical portion 34 is energized in the upper direction by thespring, etc. (not shown), and is moved in the lower direction along theaxis only when the bending lever 13 is lowered, thereby pressing andswitching on the tactile switch 35 at the bottom. Only when thespherical portion 34 is lowered, the tactile switch 35 outputs anon-signal to the CPU 42. The spherical portion 34 is energized to beautomatically returned to the neutral position by the spring, etc. (notshown).

The CPU 42 outputs the positional information at levels corresponding tothe inclination angles in the up and down and right and left directionsof the bending lever 13 to the control circuit 43 via the remotecontroller cable 15, and also outputs the on-signal of the tactileswitch 35 to the control circuit 43 as a mode switching signal.

The control circuit 43 can control each section of the endoscope controlunit 45, similarly to the control circuit 7 in FIG. 1. The controlcircuit 43 incorporates a system control microcomputer or CPU 46 forcontrolling the motor drive circuit 8 to control the bending angle ofthe bending portion 5 b of the inserted portion 2 depending on theinclination angle of the bending lever 13. Further, in the presentembodiment, the CPU 46 in the control circuit 43 can execute not only apositional control mode for controlling the bending angle depending onthe inclination angle of the bending lever 13 but also a speed controlmode for proportioning the inclination angles of the bending lever 13 torotational speeds of the motors 27 (refer to FIG. 2). Incidentally, thebending direction conforms to the inclining direction of the bendinglever 13 in any mode.

In the present embodiment, the CPU 46 in the control circuit 43 switchesthese modes by a switch signal based on the on-signal of the tactileswitch 35. In other words, when the CPU 46 in the control circuit 43receives the switch signal in the positional control mode and when it isdetected based on the positional information that the bending lever 13is returned to the neutral position after receiving the switch signal,the CPU 46 transmits a switch command from the positional control modeinto the speed control mode to the motor drive circuit 44. When theswitch signal is received in the speed control mode, the CPU 46 in thecontrol circuit 43 transmits a switch command from the speed controlmode into the positional control mode to the motor drive circuit 44.

The motor drive circuit 44 incorporates a motor drive controlmicrocomputer or CPU 47. The motor drive circuit 8 receives the modeswitch command from the control circuit 43 in the CPU 47.

When the mode switching command is received, the CPU 47 keeps the laststatus in the mode and switches a program to thereafter execute the modeafter switch.

For example, when the switch command is received in the positionalcontrol mode, the CPU 47 keeps a bent state (bending angle) of thebending portion 5 b and simultaneously switches an internal program tothe speed control mode for proportioning the inclination angle of thebending lever 13 to the rotational speed of the motor 27 thereafter.

On the contrary, when the switch command is received in the speedcontrol mode, the CPU 47 thereafter switches the program to thepositional control mode for proportioning the inclination angle of thebending lever 13 to the bending angle of endoscope.

Incidentally, it is considered that, frequently, the bending lever 13 isreturned to the center position at the time of switching from the speedcontrol mode to the positional control mode. In this case, the bentstate at the time of switching the mode is returned to a straight statein the positional control mode.

If the speed is high when the bent state is returned to the straightstate, a mechanical load is increased and a video image is suddenlydisplayed, thereby making it difficult to grasp an observed position.Therefore, preferably, the return speed to the straight state isrelatively slow.

Then, when switching from the speed control mode to the positionalcontrol mode, the CPU 47 relatively decreases a rotational speed of themotor 27, and slowly returns the bending state up to the bending anglecorresponding to the inclination angle of the bending lever 13 at thetime of straight state or mode switching. Incidentally, the bendingspeed can be arbitrarily selected in this case and is controlled to aproper bending speed and, thereby, durability and usability can beimproved.

The CPU 47 controls the speed of the motor 27 in the speed control modebased on a value obtained by integrating the positional information(value) outputted in proportional to the inclination angle of thejoystick.

Incidentally, the relationship between the inclination angle of thelever and the bending angle in the positional control mode is notnecessarily proportional and the relationship between the inclinationangle of the lever and the rotational speed of the motor in the speedcontrol mode is not necessarily proportional. The bending angle and therotational speed may be increased and decreased by increasing anddecreasing the inclination angle of the lever based on, for example, anexponential function or another calculating formation.

Incidentally, a rotational speed V_(m) and a rotational angle θ_(m) ofthe motor in the speed control mode are expressed by the followingformulations (1) and (2). $\begin{matrix}{V_{m} = {K\left( {{\theta (t)} - \theta_{0}} \right)}} & (1) \\{\theta_{m} = {\int_{0}^{t}{{K\left( {{\theta (t)} - \theta_{0}} \right)}{t}}}} & (2)\end{matrix}$

where K is constant, t is time when the joystick is inclined, θ(t) isthe inclination angle after time t, and θ₀ is the angle at the neutralposition of the joystick.

Next, operation of the embodiment with the above constitution will bedescribed referring to FIG. 7.

Herein, assume that the operator bends the bending portion 5 b of theinserted portion 2. Incidentally, assume that at this point, the CPU 46in the control circuit 43 has set the mode to the positional controlmode. The operator inclines the bending lever 13 of the joystick 31incorporated in the operational remote controller 41, thereby performingthe bending operation.

When the operator inclines the bending lever 13, a signal having a levelcorresponding to the inclination angle is supplied to the CPU 42. TheCPU 42 generates the positional information based on the input signaland transmits the generated positional information to the controlcircuit 43 via the remote controller cable 15.

The CPU 46 in the control circuit 43 controls the motor drive circuit 44based on the received positional information (step S2). Thus, the CPU 47in the motor drive circuit 44 servo controls the motor 27 in accordancewith the positional information (step S3), and drives the motor at apredetermined speed for inclining the bending portion 5 b (step S4).

Herein, assume that the operator reduces the bending speed and, thereby,the bending angle is finely adjusted. In this case, the operator loweresthe bending lever 13. As a result of this operation, the tactile switch35 of the joystick 31 is turned on, and the CPU 42 generates the switchsignal. The CPU 46 in the control circuit 43 receives the switch signal.

Thus, the CPU 46 in the control circuit 43 shifts the process from stepS1 to step S5, whereupon the CPU 46 makes the motor drive circuit 44keep the bent state. Further, when the operator returns the bendinglever 13 to the neutral position, or the finger is apart from thebending lever and the bending lever is automatically returned to theneutral position, the CPU 46 in the control circuit 43 detects that thebending lever 13 is located at the neutral position based on thepositional information (step S7). The CPU 46 outputs a switch commandfrom the positional control mode into the speed control mode to the CPU47 in the motor drive circuit 44.

The CPU 47 in the motor drive circuit 44 controls driving of the motors27 by the speed control mode S6 in which the bending speed is controlledin accordance with the bending angle of the bending lever 13. When theoperator inclines the bending lever 13 with a relatively small angle,the motor drive circuit 44 servo controls the motor (step S3) and,thereby bending the bending portion 5 b at a low speed corresponding tothe inclination angle of the bending lever 13 (step S4). Thus, theoperator can finely adjust the bending angle of the bending portion 5 b.

Next, assume that the operator lowers the bending lever 31 in the axialdirection to return the mode to the original positional control mode.Then, the tactile switch 35 is turned on, whereupon the CPU 46 in thecontrol circuit 43 receives the switch signal. The control circuit 43outputs a switch command from the speed control mode into the positionalcontrol mode to the motor drive circuit 44.

The motor drive circuit 44 slowly changes bending angle of the bendingportion 5 b up to the bending angle corresponding to the inclinationangle of the bending lever 13 at the time of outputting the switchcommand. According to a general using method, it is considered that atthe switching time into the positional control mode, the bending lever13 is located almost at the neutral position by energization of thespring. Therefore, the motor drive circuit 44 slowly returns the bendingportion 5 b to the straight state.

When the bending angle of the bending portion 5 b changes up to theangle corresponding to the inclination angle of the lever 13 at the timeof outputting the switch command, the CPU 46 in the control circuit 43thereafter performs the positional control to bend the bending portion 5b to correspond to the inclined position of the bending lever 13 at anormal speed.

As mentioned above, in the present embodiment, with simple operation,the operator can arbitrarily switch, the positional control methodwhereby the operator can easily grasp the actual bending angle and thespeed control method whereby the fine adjustment is possible and theoperator can arbitrarily change the bending speed, thereby using theswitched method.

Incidentally, in the second embodiment, the CPU 46 in the controlcircuit 43 determines that the bending lever returns to the neutralposition. After returning the bending lever to the neutral position, theCPU 46 transmits the switch command to the CPU 47 in the motor drivecircuit 44. In contrast, the CPU 47 in the motor drive circuit 44 maydetermine that the bending lever returns to the neutral position. Morespecifically, in this case, the CPU 46 in the control circuit 43supplies the switch command and information corresponding to theinclination angle of the bending lever to the CPU 47 in the motor drivecircuit 44. After it is detected that the bending lever is returned tothe neutral position, the CPU 47 switches the mode.

FIG. 8 is a flowchart showing operational flow used into the thirdembodiment of the present invention. Referring to FIG. 8, the samereference numerals as those in FIG. 7 denote the same processing routinein FIG. 7 and the description is omitted.

The configuration of a hardware in the present embodiment is similar tothat of the second embodiment.

In the present embodiment, at the time of switching from the positionalcontrol mode into the speed control mode, even if the bending lever isnot returned to the neutral position, the mode shifts.

The operational flow in FIG. 8 differs from that in FIG. 7 in that stepS8 is added whereupon it is determined whether or not a predeterminedtime passes after lowering the bending lever 13 in the axial direction.

In the present embodiment, with the above-mentioned constitution, afterthe operator lowers the bending lever 13 in the axial direction, whenthe bending lever 13 is not returned to the center position after thepredetermined time fixed on the program passes, the CPU 46 in thecontrol circuit 43 detects that the predetermined time passes in stepS8. Then, the CPU 46 in the control circuit 43 automatically outputs theswitch command from the positional control mode into the speed controlmode.

Therefore, in the present embodiment, when the bending direction of thebending portion 5 b at the time of switching the mode coincides with thebending direction of the bending portion 5 b after switching the mode,smooth bending operation becomes possible at the time of switching thecontrol mode.

As mentioned above, in the present embodiment, in the cases ofcontinuously observing one direction, etc., the control modes can beswitched smoothly and continuously. Also, the processing routine can besimplified.

FIG. 9 is a block diagram showing the fourth embodiment of the presentinvention. Referring to FIG. 9, the same reference numerals as those inFIG. 5 denote the same components in FIG. 5 and the description isomitted. Differently from the second and third embodiments, in thepresent embodiment, the operator can recognize a locked state ofbending.

An endoscope control unit 51 has a constitution almost similar to thatof the endoscope control unit 45 in FIG. 5, excluding a point that adisplay function for indicating the locked stage of bending is added.More specifically, a bending drive device 68 corresponds to the motor 27and the wires 28 for traction in FIG. 2 and drives the bending of thebending portion 5 b of the inserted portion 2. A bending controlsubstrate 66 has a function corresponding to the motor drive circuit 44in FIG. 5 and controls the bending drive device 68 based on theoperation of the operational remote controller 41 while switching thepositional control mode and the speed control mode.

A CCU 67 has a constitution similar to that of the CCU 6 in FIG. 5. Asystem control microcomputer 61 has an equivalent function to that ofthe control circuit 43 in FIG. 5. The system control microcomputer 61comprises: the CPU 62; a ROM 63; an image generating device 64; and asuperimposing device 65.

The ROM 63 stores therein an operational program of the CPU 62. The CPU62 has an equivalent function to that of the CPU 46 in the controlcircuit 43 in FIG. 5. Information indicating that a state shifts to thelocked state of bending is supplied in response to the switch commandfrom the bending control substrate 66. The CPU 62 outputs a displaycommand based on the information to the image generating device 64. Wheninputting the display command accompanied by the locked state ofbending, the image generating device 64 generates display data ofdisplay (character or graphic) indicating the lock against bending forsupplying the generated data to the superimposing device 65.

The superimposing device 65 superimposes the display data from the imagegenerating device 64 to an image formed in the CCU 67 for outputting thesuperimposed data to the monitor 9.

In the present embodiment, with the above-mentioned constitution,similarly to those in the second and third embodiment, when the operatorlowers the bending lever 13 in the operational remote controller 41, thetactile switch (refer to FIG. 6) is turned on whereupon the switchsignal is supplied to the CPU 62. When the switch signal is received,the CPU 62 outputs a switch command for switching the mode to thebending control substrate 66.

In association with the switching of the mode, the bending controlsubstrate 66 controls the bending drive device 68, thereby locking thebent state of the bending portion 5 b (locking the bending). In thepresent embodiment, the bending control substrate 66 supplies theinformation indicating that a state shifts to the locked state of thebending to the CPU 62 in the system control microcomputer 61.

Thus, the CPU 62 outputs the display command to the image generatingdevice 64. The image generating device 64 generates the display dataindicating the lock against bending for supplying the generated data tothe superimposing device 65. The superimposing device 65 superimposesthe display data indicating the locking against bending to the imagefrom the CCU 67 for outputting the superimposed data to the monitor 9.

As mentioned above, a display 69 indicating the lock against bendingdisplays the superimposed image onto a display screen of the monitor 9.When the bending control substrate 66 cancels the lock against thebending, the CPU 62 executes an instruction for stopping an output ofthe display data on the image generating device 64. Thus, the display 69indicating the lock against bending is erased from the display screen inthe monitor 9.

As described above, in the present embodiment, display indicating thelocked state of the bending can be displayed on the monitor and theoperator can easily confirm the locked state of the bending. The displayindicating the locked state of the bending is superimposed onto theimage from the CCU 67. The operator can easily confirm the locked stateof the bending without taking his eyes off the endoscope image.

Incidentally, the present embodiment shows an example in which thebending control substrate 66 outputs a signal indicating the completionof locking operation of bending to the CPU 62 and, thereby, the CPU 62executes the display instruction. However, the completion of lockingoperation of bending is determined by the system control microcomputer61 and then the display instruction may be executed.

FIGS. 10 to 23 relate to the fifth embodiment of the present inventionin which FIG. 10 is an overall constitution diagram showing the overallconstitution of an endoscope apparatus according to the fifth embodimentof the present invention; FIG. 11 is an explanatory view of thestructure of a drum in FIG. 10; FIG. 12 is an explanatory view showingthe structure of a motor drive in FIG. 11; FIG. 13 is a front viewshowing an operational remote controller according to the fifthembodiment of the present invention; FIG. 14 is a back view showing theoperational remote controller; FIG. 15 is a side view showing theoperational remote controller; FIG. 16 is an upper end view showing anupper end of the operational remote controller; FIG. 17 is a lower endview showing a lower end of the operational remote controller; FIG. 18is a cross-sectional view showing the operational remote controller;FIG. 19 is an explanatory view showing various structures of a bendinglever; FIG. 20 is a constitutional cross-sectional view showing theconstitution of a slide switch of the operational remote controller;FIG. 21 is an explanatory view showing the structure of a microphone ofthe operational remote controller; FIG. 22 is an explanatory viewshowing the relationship between a connector for LCD and a cable in theoperational remote controller; and FIG. 23 is a block diagram showingthe relationship between the operational remote controller and anendoscope main body.

In the present fifth embodiment, in addition to a joystick almostsimilar to the joysticks described in the above first to fourthembodiments, an endoscope having an operational remote controller(operational remote controller for endoscope) which is provided with keyswitches for various operations will be described.

As shown in FIG. 10, an endoscope apparatus 101 according to the presentfifth embodiment having an endoscope main body 104 comprising a longinserted portion 102 and a drum unit 103 winding and accommodating theinserted portion 102. A monitor 105 is connected to the drum unit 103 inthe endoscope main body 104. Further, an operational remote controller106 is connected to the drum unit 103 in the endoscope main body 104.

An adapter 107 as an end having image pickup means and illuminatingmeans (both not shown) can be detachably attached to the insertedportion 102. The adapter 107 comprises a plurality of types of anadapter 107 a and an adapter 107 b capable converting an angle of fieldof view and a direction of field of view. A bending portion 108 capableof bending is provided at a base-end side of the adapter 107 and can bebent by operation from the endoscope main body 104 side.

The drum unit 103 comprises a drum 109 and a bed 110 which rotatablysupports the drum 109 in the axial direction. The inserted portion 102can be wound to the drum 109. The drum 109 incorporates partsconstituting a signal processing unit. The operational remote controller106 is detachably connected to the drum 109 via a connector 111. Themonitor 105 is detachably connected to the drum 109 via the connector111. The signal processing unit, etc. in the drum 109 supply a videosignal and a power to the monitor 105.

Next, the detail of the drum unit 103 will be described referring toFIG. 11.

The drum 109 has therein: a light source device 113 for supplyingillumination light to an optical fiber bundle 112, which is illuminatingmeans; and a motor drive unit 115 having two motors 114 for towing awire to operate the bending portion 108. The drum 109 also incorporatesa central substrate 116 having a control function for controlling themotor drive unit 115, a signal processing function for converting animage photographed by the image pickup means into a video signal togenerate the video signal and for recording images such as a still imageand a live image based on the video signal, and a function forcontrolling the operations of the respective functions. The monitor 105are electrically connected to the operational remote controller 106 inthe central substrate 116. The base-end side of the inserted portion 102is fixed to the motor drive unit 115. The inserted portion 102 isextended from an inserted opening. 119 pierced to a cylindrical body 118sandwiched between two side plates 117 of the drum 109.

Next, the detail of the motor drive unit 115 will be described referringto FIG. 12.

The motor drive unit 115 comprises: a supporting plate 120 for fixingthe base-end side of the inserted portion 102 and supporting a motor(not shown); two sprockets 122 fixed to an output shaft 121 of themotor; two chains 123 which is engaged with the sprockets 122 and changerotating movement of the sprockets 122 into advancing and retractingmovement; a plurality of wires 124 in which one end of each of which isfixed to the end of the chain 123 and the other end of each of which isfixed to the bending portion 108; and a plurality of coil sheaths 125for protecting the wires 124.

Incidentally, the plurality of wires 124 are four wires, which are thesame as the number of ends of the chains 123.

Next, the detail of the operational remote controller 106 will bedescribed.

As shown in FIGS. 13 to 18, the operational remote controller 106comprises a case 106 a which has a volume capable of being held by anupper cover 126 made of a resin having high crashworthiness and a lowercover 127 made of the same resin. A plurality of switches (which will bedescribed in detail) for remotely operating the endoscope apparatus 101are placed distributively on the front surface and the back surface ofthe case 106 a.

In the case 106 a, a convex portion 130 is formed at the back surfaceside in the lower end and a stepped portion 135 is formed at the frontsurface side in the upper end. A projection 131 is formed to the steppedportion 135. The convex portion 130 is provided so that the back surfaceof the convex portion 130 becomes almost plane as represented by abroken line shown in FIG. 15. Further, the plurality of switches (whichwill be described in detail) provided at the front surface side of thecase 106 a are placed in a range shown by a dashed line connecting theprojection 131 and the lower end. Thus, even if the front surface sideis directed underneath and is placed on a desk, etc., the operationalremote controller 106 erroneously does not operate if erroneouslypressing the switches and the switches can be protected if theoperational remote controller 106 is wrongly fallen. Also, since theupper cover 126 and the lower cover 127 are made of the resin having thehigh crashworthiness, the operational remote controller 106 is notbroken if it is wrongly fallen.

The front surface side of the operational remote controller 106 will bedescribed mainly referring to FIGS. 13, 15, 17, and 18.

In order to enable the use of the operational remote controller 106 bygrasping it by either of the right and left hands, on the front surfaceof the operational remote controller 106, a bending lever 128 of thejoystick 145 is placed at a slightly upper side from the center on thefront surface, an instructing lever 129 is placed at the center on thefront surface, a recording button 138 a is placed at the lower side ofthe instructing lever 129, further, a call button 138 b is placed at thelower side of the recording button 138 a, and a power source button 139is placed at the lower side of the call button 138 b, each of which isplaced on the central axis of the upper cover 126.

Also, on the surface of the operational remote controller 106, abrightness button 132 a and menu button 132 b are placed at the rightand left of the central axis of the upper cover 126 at the upper side ofthe bending lever 128. The bending lever 128 is placed at a positionwhere it is easily operated by the thumb. Also, each lever and otherbuttons are placed within a range in which the thumb reaches them.

A center button 136 for operating the bending portion 108 to bestraight-shaped is provided near the bending lever 128 on the surface ofthe upper cover 126. The center button 136 is provided to be slightlyconcaver than the surface of the upper cover 126 so as not to touch thecenter button 136 erroneously at the time of operating the bending lever128.

The brightness button 132 a is a button for adjusting the brightness ofa photographed image. The menu button 132 b is a button for displayingor non-displaying the menu. When the operator lowers the menu button 132b, menus are overlappingly displayed on an observed screen displayed onthe monitor 105. Among the menus displayed on the monitor 105, when theoperator changes the brightness and enhancement of the image, theobserved screen displayed on the monitor 105 corresponding to thechanges is changed corresponding to the operation.

The instructing lever 129 can switch menu modes. For example, theoperator pushes down in vertical and horizontal directions and, thereby,an item in the menu can be selected. Also, the operator pushes theinstructing lever 129 and, thereby, the item in the menu can bedetermined. Incidentally, the instructing lever 129 functions as aswitch for selecting the menus when the menus are displayed. By pushingdown in the vertical and horizontal directions or askew direction whenthe observed image is displayed on the monitor 105, the instructinglever 129 can cause the screen to be panned or tilted (can select aportion where a zoom screen is to be displayed on the monitor 105).

The bending lever 128 is a lever for bending the bending portion 108.When the bending lever 128 is lowered in the axial direction, thebending portion 108 changes to the locked state, thereby switching themode as mentioned in the first to fourth embodiments.

The recording button 138 a is a button for recording a still image or alive image. The operation of the recording button 138 a enables aninstruction for recording the still image when a freeze screen isdisplayed on the monitor 105, and also enables an instruction forrecording the live image when the observed screen is displayed on themonitor 105.

The call button 138 b is a button for instructing a call of a recordedimage. The operation of the call button 138 b enables a thumbnail imageto be displayed. The power source button 139 is a button having afunction for turning on/off the overall power source.

On the stepped portion 135 at the upper side of the upper cover 126, aplurality of microphone holes 133 for inputting an audio sound and anindicator 134 for displaying the turn-on the power source are placed.

At the lower side of a held portion 140 in the operational remotecontroller 106, a connector for LCD 141 which connects externalequipment other than the LCD monitor and a soft cable 142 which isconnected to a connector 111 connected to the endoscope main body 104are provided.

The stepped portion 135 is stepped against the held portion 140 with aheight to prevent erroneous operation of the brightness button 132 a andthe menu button 132 b at the time of operating the bending lever 128. Byarranging the brightness button 132 a and the menu button 132 b whichare frequently used on the stepped portion 135, the usability of theoperational remote controller 106 is improved. Also, by arranging thebrightness button 132 a and the menu button 132 b on arc centered thecenter position of the instructing lever 129, the operational remotecontroller 106 is easily operated by the holding thumb.

Sequentially, the back surface side of the operational remote controller106 will be described mainly referring to FIGS. 14, 15, 16, and 18.

The lower cover 127 on the back surface of the operational remotecontroller 106 is constituted in a shape enabling the holding by eitherof right and left hands. At the upper side of the lower cover 127, ahanger 143 and a slide switch 144 capable of the holding by either ofright or left hand are arranged on the central axis of the lower cover127.

The hanger 143 is used when the operational remote; controller 106 ishung on a hooked member (not shown). Since the hanger 143 is provided ata balanced place, the operational remote controller 106 is straight hungdown without inclination even if it is hung on the hooked member.

The slide switch 144 is a switch for inputting an instruction foradjusting magnification of the observed image, thereby enablingleft-inclination operation or right-inclination operation. Operation ofthe slide switch 144 enables output of an instruction for continuousenlarging or reducing the observed image displayed on the monitor 105.The central substrate 116 displays a slide bar on the observed screen ofthe monitor 105 in accordance with the instruction from the slide switch144, thereby displaying a zoom ratio. On the other hand, if nooperational instruction is outputted from the slide switch 144, thecentral substrate 116 does not enable the slide bar to be displayed onthe observed screen of the monitor 105.

The overall constitution of the operational remote controller 106 willbe described referring to the drawings.

As shown in FIG. 15, the bending lever 128 placed at the front surfaceside of the case 106 a and the slide switch 144 placed at the backsurface side of the case 106 a are arranged at positions where it ismost operable by the thumb and the forefinger, respectively. The bendinglever 128 is higher than the instructing lever 129 when viewed from thelower side of the case 106 a, and the bending lever 128 is provided atthe most operable position.

Further, the upper end of the bending lever 128 differs from that of theinstructing lever 129 in shape, as shown in FIGS. 15 and 18. The bendinglever 128 is concave-shaped to easily hang the finger. The upper end ofthe instructing lever 129 is spherical-shaped.

Incidentally, the upper-end shapes of the levers can be varied to matchwith various operations, for example, a touch portion La is spherical asshown in FIG. 19(a); a touch portion Lb is columnar as shown in FIG.19(b); a touch portion Lc is cone-shaped as shown in FIG. 19(c); and atouch portion Ld is formed by piling up discs, thus beingtriangular-shaped with a step when viewed from the side surface as shownin FIG. 19(d).

The connector 141 for LCD and the cable 142 are horizontally aligned asshown in FIG. 17. A cable connected to the connector 141 for LCD (notshown) and the cable 142 are extended in the same direction. Therefore,it is not impeditive for each cable. Of course, as shown in FIG. 24,which will be described hereinafter, when both cables exist, thesecables are bound by a binding member 220 and, thereby, it is moreuser-friendly.

Next, the interior of the operational remote controller 106 will bedescribed mainly referring to FIG. 18.

As mentioned above, the case 106 a of the operational remote controller106 comprises the upper cover 126 and the lower cover 127. The case 106a contains: the menu button 132 b; the indicator 134; the recordingbutton 138 a; the call button 138 b; the power source button 139; thejoystick 145; a plurality of tactile switches 147; an instructing switch148; a lever switch 150; a lever switch substrate 151; an LED 152; anLED substrate 153; a relay substrate 154; a switch substrate 155; asignal line 156; and a connector 157 for substrate. The cable 142 ispull out from the case 106 a.

Further, the slide switch 144 comprises a rubber cover 149 made of asoft rubber material and the lever switch 150. The rubber cover 149 hasflexibility without interference with the operation of the lever switch150 and prevents ingress of waterdrop and dust in the case 106 a.Further, the lever switch 150 can be inclined at the right and left asshown by an arrow J in FIG. 20, and can be lowered in the axialdirection-as shown by an arrow K in FIG. 20, that is, it is a switchcapable of outputting signals corresponding to various operations.

As shown in FIG. 20, the lever switch 150 incorporates a lever portion161. The lever portion 161 is assembled to one part in the rubber cover149. A buckled portion 162 is provided to the rubber cover 149 toimprove the operability.

A switch opening 159 is penetrated in an area to which the bending lever128 of the upper cover 126 is placed. A rubber boot 160 is placed to theswitch opening 159. The rubber boot 160 has flexibility withoutinterference with the bending operation of the bending lever 128 andprevents ingress of waterdrop and dust in the case 106 a.

The joystick 145 is an input device for outputting an analog signalcorresponding to an angle of the bending lever 128. When the bendinglever 128 is lowered in the axial direction, the joystick 145 alsooutputs an on-signal through the tactile switch 147. More specifically,the joystick 145 is an analog typed joystick by which an output signalis varied corresponding to a slant angle of an operational shaft 145 a.When the operational shaft 145 a is lowered in the axial direction, thetactile switch 147 for generating a signal is provided to the joystick145. In place of the analog joystick, a digital joystick comprising anoperational shaft and an on/off switch provided corresponding to adirection in which the operational shaft is slanted may be constituted.When the operational shaft has the slant angle, the digital joystick canoutput the on-signal corresponding to the direction in which the leveris slanted among four directions of X- and Y-directions.

Incidentally, the joystick 145 is automatically returned to theperiphery of a predetermined neutral position by an energizing force ofa spring, etc. (not shown), similarly to a manner described in the firstto fourth embodiments. The control similar to that in the description ofthe first to fourth embodiments is performed.

When the instructing lever 129 is lowered in the axial direction, theinstructing switch 148 outputs another independent on-signal.

By pressing the recording button 138 a, the call button 138 b, the powersource button 139, the menu button 132 b, and the brightness button 132a (not shown), the tactile switch 147 of each of the buttons can outputthe on-signal.

The lever switch 150 is mounted to the lever switch substrate 151. TheLED 152 and the tactile switches 147 corresponding to the brightnessbutton 132 a and the menu button 132 b are mounted to the LED substrate153. The connector 157 for substrate is mounted to the relay substrate154. The connector 157 for substrate is connected to the signal line 156of the cable 142. The respective tactile switches 147 corresponding tothe recording button 138 a, the call button 138 b, and the power sourcebutton 139 are placed to the switch substrate 155. The lever switchsubstrate 151, the LED substrate 153, and the switch substrate 155 areelectrically connected to the relay substrate 154 via an FFC cable, etc.

A frame 158 is bent-shaped to attach parts having different heights. Thejoystick 145, the relay substrate 154, the switch substrate 155, and thecable 142 are attached to the frame 158. The frame 158 is fixed to theupper cover 126, thereby receiving a thrust force at the time ofoperating the recording button 138 a, the call button 138 b, the powersource button 139, the joystick 145, and the instructing switch 148.

As shown in FIG. 18, the recording button 138 a and the call button 138b are arranged on the almost same surface as the front surface of theheld portion 140 to prevent erroneous pressing. The power source button139 is provided slightly lower than the front surface of the heldportion 140 to prevent the erroneous pressing as shown in FIG. 18.

A sealing structure that an elastic member to prevent the ingress of thewaterdrop and dust is partly pressed is formed at all buttons providedto the surface of the case 106 a and the respective openings provided toplace the connector 141 for LCD and the cable 142. Similarly, theelastic member is pressed to a seam between the upper cover 126 and thelower cover 127, thereby preventing the ingress of the waterdrop anddust.

The indicator 134 is made of a light-transmittable lacteous resin andhas a structure as shown in FIG. 18. The indicator 134 is located at theposition opposed to the LED 152. Incidentally, as the LED 152, forexample, a green-luminant is used. In the case 106 a, the convex portion130 and the stepped portion 135 form an internal space which functionsas a type of bumper. Only the above-mentioned member is arranged in thecase 106 a and the case 106 a has a light weight.

As shown in FIG. 21, the microphone holes 133 are provided for thestepped portion 135 in the case 106 a. A microphone 164 is disposed atthe position corresponding to the microphone holes 133. The microphone134 is electrically connected to the LED substrate 153 via a lead wire.In the microphone holes 133, a film 165 for transmitting a sound andpreventing the ingress of liquid, dust, etc. is provided at the interiorside of the case 106 a.

An example in which an LCD monitor 167 is connected via the connector141 for LCD in the operational remote controller 106 will be describedreferring to FIG. 22.

The signal line 156 of the cable 142 is connected to the connector 157for substrate, and a part of the signal line 156 is connected to theconnector 141 for LCD. Through the connector 141 for LCD, a power, avide signal, and an audio signal are supplied from the endoscope mainbody 104.

The LCD monitor 167 is connected to the endoscope main body 104 byinsert-connecting a connector 169 provided for the tip of the cable 168to the connector 141 for LCD. Thus, the power is supplied to the LCDmonitor 167 and also the video signal and the audio signal are supplied,thereby displaying a desired observed image and outputting an audiosound. Incidentally, in place of the LCD monitor 167, a face mounteddisplay FMD (or called an HMD (Head Mounted Display) may be employed.

Next, the relationship among the monitor 105, the operational remotecontroller 106, and the endoscope main body 104 will be describedreferring to FIG. 23.

The relay substrate 154 is arranged in the operational remote controller106. The joystick 145, the tactile switches 147, the instructing switch148, and other parts are connected to the relay substrate 154. The relaysubstrate 154 has: an A/D converter; and a CPU to control the joystick145 similarly to the control in the description in the first to fourthembodiments and for various calculating processes; and an audioamplifier, which are not shown. As shown in FIGS. 11 and 12, the relaysubstrate 154 is connected to the central substrate 116 provided in thedrum 109 via the cable 142.

As shown in FIG. 12, in the drum 109, the central substrate 116 iselectrically connected to motors 114 in the motor drive unit 115. Themonitor 105 is connected to central substrate 116 via the cable. Theconnector 141 for LCD is connected to the central substrate 116 via thecable 142. The central substrate 116 receives a signal from the imagepickup means at the tip of the inserted portion 102 and signal-processesthe received signal to supply a video signal to the monitor 105. Thecentral substrate 116 fetches various instructing signals from the relaysubstrate 154, then, the motors 114 in the motor drive unit 115 issubjected to control similar to that in the first to fourth embodiments,and the central substrate 116 controls various functions of theendoscope apparatus 101.

Function of the endoscope apparatus 101 and the operational remotecontroller 106 having the above constitution will be described.

The power source button 139 is pressed, thereby turning on the powersource, then, a power is supplied to each portion from the power source(not shown), thereby lighting on the LED 152. The indicator 134 as apilot lump is green lit on.

After the operator confirms the above operation, he pulls out theinserted portion 102 which winds to the drum 109. The operatorphotographs an observed target by using the image pickup means providedfor the end of the inserted portion while one-hand holding the insertedportion 102 and viewing the front of the observed target by usingilluminating means provided for the end of the inserted portion. Then,the image of the observed target is displayed on the monitor 105. Inthis case, the operator changes from the adapter 107 a to the adapter107 b if required, and observes the target by changing a direction of afield of view and an angle of filed of view.

Next, an operating method of each operating means will be described.

(Holding Operation of the Held Portion 140)

As shown in FIGS. 13 and 14, the operator one-handed holds the heldportion 140 of the case 106 a in the operational remote controller 106.The operator places his thumb of his hand grasping the grasped portion140 to the bending lever 128 and also places the forefinger of his handgrasping the grasped portion 140 to the slide switch 144.

(Operation of the Bending Lever 128)

The operator keeps the held state of the operational remote controller106 while observing the monitor 105, and inclines the bending lever 128in a direction to be observed in the screen displayed on the monitor105. Then, the joystick 145 is moved corresponding to an amount ofoperation of the bending lever 128, and outputs a signal indicating theamount of movement in the X- and Y-directions corresponding to theamount of operation. The signal indicating the amount of movement in theX- and Y-directions is changed into a rotational direction controlsignal of the motors in the relay substrate 154 and is supplied to thecentral substrate 116. A predetermined amount of power is supplied tothe motors 114 of the motor drive unit 115 in the central substrate 154based on the rotational direction control signal. Thus, the motors 114rotate and tow the wire 124. The bending portion 108 is bent in theoperated direction.

(Operation for Pressing the Bending Lever 128 in the Axial Direction)

When the operator desires the bending to be fixed, he presses thebending lever 128 in the axial direction. Then, a signal is outputtedfrom the tactile switch 147 in the joystick 145 and passes from therelay substrate 154, through the wire 124 and the central substrate 116,whereupon the motor drive unit 115 fixes the bending operation. In thiscase, when adjusting the bending angle, a function to be operated may beassigned to the tactile switch 147 in the joystick 145. For example,when the bending portion 108 is in a desired bent state and the operatorsimultaneously assigns a function for fixing the bent state to thetactile switch 147 in the joystick 145, he can operate the bending lever128 without unhanding the bending lever 128 from his thumb. Also, whenthe operator assigns a mode switching function to the tactile switch 147in the joystick 145, in the positional control mode, he can operate forswitching the mode from the positional control mode to the speed controlmode without unhanding the bending lever 128 from his thumb.

(Operation of the Slide Switch 144)

The operator can operate the slide switch 144 through three operationsof left inclination, right inclination, and pressing of the center byusing his forefinger while holding the held portion 140 in theoperational remote controller 106. Then, a signal is transmitted to thecentral substrate 116 via the relay substrate 154, similarly to theoperation of the bending lever 128. As a consequence, the operator canoperate the functions of the endoscope apparatus 101. For example, bypressing the center of the slide switch 144, the operator assigns afunction for obtaining a still image to the slide switch 144. Also, bypressing a portion of the left inclination, the operator assigns afunction for enlarging the observed image during observation to theslide switch 144. Further, by pressing a portion of the rightinclination, the operator assigns a function for reducing the observedimage to the slide switch 144. When assigning the functions to the slideswitch 144 as mentioned above, fast operation is possible while holdingthe held portion 140. Therefore, the usability is improved.

(Operation of the Center Button 136)

The operator can operate the center button 136 by moving his thumb whileholding the held portion 140 of the case 106 a in the operational remotecontroller 106. The above operation is performed, whereupon the tactileswitch 147 operates, thereby supplying a signal to the central substrate116 from the relay substrate 154. Thus, the central substrate 116rotates the motors 114 in the motor drive unit 115, then, tows the wire124, and the bending portion 108 becomes straight. When an image otherthan the center of the image is displayed, the image in the center ofthe image is displayed on the monitor 105.

(Operation of the Brightness Button 132 a and the Menu Button 132 b)

The operator presses the brightness button 132 a or menu button 132 b byunhanding and moving his thumb from the bending lever 128 while holdingthe held portion 140 of the case 106 a in the operational remotecontroller 106. When pressing the brightness button 132 a, aninstructing signal outputted from the tactile switch 147 is inputted tothe central substrate 116 via the relay substrate 154. Thus, the centralsubstrate 116 brightens or darkens the video signal. When pressing themenu button 132 b, an instructing signal outputted from the tactileswitch 147 is inputted to the central substrate 116 via the relaysubstrate 154. Thus, the menu is displayed on the observed imagedisplayed on the monitor 105. Incidentally, when the menu is displayed,the brightness button 132 a may function as a button for returning alayer of the menu to a one-previous menu.

(Operation of the Instructing Lever 129)

The operator performs the following operation by moving only his thumbfrom the bending lever 128 to the instructing lever 129 while holdingthe held portion 140 of the case 106 a in the operational remotecontroller 106. First, when the operator inclines the instructing lever129 vertically and horizontally, the instructing switch 148 operatescorresponding to the inclination, thereby outputting the instructingsignal corresponding to this operation. The instructing signal generatedby the instructing switch 148 is supplied to the central substrate 116via the relay substrate 154. The central substrate 116 selects an itemof the menu based on the instructing signal. By lowering the instructinglever 129 in the axial direction, the instructing switch 148 outputs anon-signal in accordance with this operation. The on-signal is suppliedto the central substrate 116 from the relay substrate 154. The centralsubstrate 116 determines the menu by inputting the on-signal.

When a cursor is displayed on the screen of the monitor 105, the cursormay be moved by the signal from the instructing switch 148 which iscaused by operation of the instructing lever 129. Also, the operationfor pressing the instructing lever 129 in the axial direction may beused as a function of the menu button 132 b. Then, operation for allmenus can be performed by the single instructing lever 129.

(Operation of the Recording Button 138 a and the Call Button 138 b)

The operator moves his thumb from the bending lever 128 to the recordingbutton 138 a or call button 138 b while holding the held portion 140 ofthe case 106 a in the operational remote controller 106. Herein, theoperator presses the recording button 138 a and, thereby, thecorresponding tactile switch 147 operates. Then, an instructing signaloutputted from the tactile switch 147 is supplied to the centralsubstrate 116 via the relay substrate 154. When the freeze screen isdisplayed on the monitor 105, the central substrate 116 allows the stillimage to be recorded, and when the observed screen is displayed on themonitor 105, the central substrate 116 allows the live image to berecorded.

The operator presses the call button 138 b and, thereby, thecorresponding tactile switch 147 operates. Then, an instructing signaloutputted from the tactile switch 147 is supplied to the centralsubstrate 116 via the relay substrate 154. The central substrate 116allows the recorded image to be called.

Since the recording button 138 a and the call button 138 b are locatednear the instructing lever 129, the usability is improved by assigningan associated function to the instructing lever 129.

Although the specific functions are assigned to the respective leversand respective switches, the present invention is not limited to theabove description. Another function may be assigned so as to reduce thenumber of jobs or errors.

As mentioned above, the following advantages are obtained according theembodiments of the present invention.

(i) According to the embodiments of the present invention, an importantswitch or lever is placed symmetrically and, therefore, the usability isexcellent if using the switch or lever by either of right and lefthands.

(ii) According to the embodiments of the present invention, a heavysubject such as a motor is not placed in the case 106 a in theoperational remote controller 106 and, therefore, the size is reducedand the weight is also reduced.

(iii) According to the embodiments of the present invention, allswitches can be operated by the thumb and the forefinger of one handand, therefore, operation necessary for observation and inspection bythe endoscope apparatus 101 is usable.

(iv) According to the embodiments of the present invention, erroneousoperation of the buttons is prevented by the positions, the placedstate, and the functions and, therefore, erroneous operation isprevented.

(v) According to the embodiments of the present invention, theprotecting space is formed by the lower side of the case 106 a and theprojection 131 and, therefore, breakdown of the levers due to falling,etc. can be avoided.

According to the fifth embodiment of the present invention, although themonitor 105 is formed separately from the operational remote controller106, the LCD display panel may be mounted to the operational remotecontroller 106 so long as the purpose is reduction in size and weight.

FIGS. 24 to 27 relate to the sixth embodiment of the present inventionin which FIG. 24 is a side view showing an operational remote controlleraccording to the sixth embodiment of the present invention; FIG. 25 is across-sectional view showing one part of the operational remotecontroller in FIG. 24; FIG. 26 is a lower end view showing a lower endof the operational remote controller; and FIG. 27 is an upper end viewshowing an upper end of the operational remote controller.

In an operational remote controller 201 according to the present sixthembodiment, a bending lever 202 is similar to that of the fifthembodiment. The operational remote controller 201 differs from that ofthe fifth embodiment in that two buttons (a freeze button 203 and arecording button 204) are placed in the longitudinal direction at thetip portion side of a lower cover 205 of a case 201 a.

More specifically, as shown in FIGS. 24, 25, and 27, the freeze button203 and the recording button 204 are provided, at different heights, toan uneven portion 206 of the lower cover 205 for the purpose ofpreventing erroneous operation. As shown in FIG. 25, in the freezebutton 203, a tact switch 209 b can be operated. The tact switch 209 bis mounted to a substrate 210 b. The substrates 210 a and 210 b aresupported by a metal subframe 211. The tact switches 209 a and 209 b areconnected to a relay substrate (not shown) via a cable (not shown). Thefreeze button 203 and the recording button 204 are subjected to aprotecting process for preventing the ingress waterdrop and drop in thecase 201 a, similarly to the above fifth embodiment.

Differently from the slide switch 144 which is adopted in the abovefifth embodiment wherein one switch functions as a plurality offunctions in the present sixth embodiment. The function is separated thefunction by the two buttons of the freeze button 203 and the recordingbutton 204 which are independent of each other and the operation isperformed by using two fingers. Thereby, probability of erroneousoperation is decreased in the present sixth embodiment.

Incidentally, when the operator lowers the freeze button 203, a sillimage is displayed on a monitor. When the operator lowers the recordingbutton 204 when a live image is displayed on the monitor, the live imageis recorded. When the operator lowers the recording button 204 when thestill image is displayed on the monitor, the still image is recorded.

As shown in FIGS. 24 and 26, a cable 207 and a connector 208 for LCD arealigned to the lower end portion of the case 201 a in the operationalremote controller 201 in the longitudinal direction.

Operation of the aforementioned operational remote controller 201 willbe described.

The operator places his thumb to the bending lever 202, his forefingerto the recording button 204, and his middle finger to the freeze button203, while one-hand holding a held portion of the case 201 a in theoperational remote controller 201.

The operator controls the bending lever 202 and, thereby, a bendingportion of an inserted portion is bent or locked.

Also, the operator presses the freeze button 203, when the operationalremote controller 201 is operated while observing the screen of themonitor. Then, the tact switch 209 a is operated and outputs a stillimage instructing signal. This still image instructing signal issupplied to the central substrate via the relay substrate. Consequently,an image displayed on the monitor becomes the still image.

The operator presses the recording button 204, when the operationalremote controller 201 is operated while one-hand holding the operationalremote controller 201 and observing the monitor. Then, the tact switch209 b is operated and outputs a recording instructing signal. Thisrecording instructing signal is supplied to the central substrate viathe relay substrate. Consequently, when the image displayed on themonitor is a still image, the still image is recorded to a recordingimage recording function. Also, when the image displayed on the monitoris an observed image, the live image is recorded to a live imagerecording function.

In the operational remote controller 201 according to the present sixthembodiment, the various buttons are placed on the central axis.Therefore, the usability is excellent in the case of using either of theright and left hands.

Also, in the operational remote controller 201 according to the presentsixth embodiment, the cable 207 and the connector 208 for LCD arealigned in the longitudinal direction, there is no interference withhand and no obstacle occur even if the operational remote controller 201is held by using either of right and left hands.

As mentioned above, according to the sixth embodiment of the presentinvention, in addition to acquisition of the advantages similar to thoseof the fifth embodiment, the following advantages are obtained.

(i) According to the sixth embodiment of the present invention, therecording button 204 and the freeze button 203 are provided at differentheights and can be certainly operated without erroneous operation.

(ii) According to the sixth embodiment of the present invention, therecording button 204 is placed on the central axis and, therefore, theusability is increased even in the case of operation using either of theright and left hand.

(iii) According to the sixth embodiment of the present invention, theconnector 208 for LCD and the cable 207 are placed to the lower endportion of the case 201 a in the longitudinal direction and, therefore,the respective cable 207 and cable for monitor become no obstacle,thereby improving the usability.

While this invention has been described in detail referring to onepreferred embodiment of the invention, it should be understood that theinvention is not limited to that precise embodiment. Rather, manymodifications and variation will be apparent to those skilled in the artwithout departing from the scope and sprit of the invention as definedin the appended claims.

What is claimed is:
 1. An endoscope apparatus comprising: an insertionportion having image pickup means and a bending portion provided at thedistal end of the insertion portion; a bending drive device having adrive source for bending the bending portion; display means fordisplaying an image picked up by the image pickup means; an operatingunit for remotely controlling the bending portion; a plurality of firstoperating members provided in a protecting space formed by a lower sideand a projection on a front surface of the operating unit; and aplurality of second operating members located on a back surface of theoperating unit.
 2. An endoscope apparatus comprising: an insertionportion having image pickup means and a bending portion provided at thedistal end of the insertion portion; a bending drive device having adrive source for bending the bending portion; display means fordisplaying an image picked up by the image pickup means; an operatingunit for remotely controlling the bending portion; and an operatingmember located on a flat portion of the front surface of the operatingunit which can select from a menu displayed on the display means.
 3. Anendoscope apparatus according to claim 1, wherein the plurality of firstoperating members are provided along a longitudinal axial direction ofthe operating unit.
 4. An endoscope apparatus according to claim 1,further comprising a hooked member for holding the operating unit at apredetermined position.
 5. An endoscope apparatus according to claim 1,wherein the plurality of first and second operating members are providedwithin an operable range when the operating the operating unit bygrasping.
 6. An endoscope apparatus according to claim 1, wherein theplurality of second operating members provided at the back surface ofthe operating unit includes a switch having a plurality of functionsaligned in the longitudinal axial direction of the operation unit.
 7. Anendoscope apparatus according to claim 1, wherein the plurality of firstand second operating members can operate at least one of a slideoperation in which an input axis is freely rotatable, and a pushoperation of the slide operation in an input axial direction.
 8. Anendoscope apparatus according to claim 1, wherein at least one of theplurality of first operating members provided at the front surface ofthe operating unit is a joystick.
 9. An endoscope apparatus according toclaim 1, wherein the plurality of first operating members provided atthe front surface of the operating unit are provided within an operablerange of a thumb of a hand when operating the operating unit bygrasping.
 10. An endoscope apparatus according to claim 1, wherein theplurality of second operating members provided at the back surface ofthe operating unit are provided within an operable range of a forefingerof a hand when operating the operating unit by grasping.
 11. Anendoscope apparatus according to claim 1, wherein the plurality ofsecond operating members provided at the back surface of the operatingunit are switches for generating at least one kind of signalscorresponding to an inclined direction of an input axis when the inputaxis is freely rotated.
 12. An endoscope apparatus according to claim 1,wherein the plurality of second operating members provided at the backsurface of the operating unit are switches are outputting a signaldifferent from a signal when an input axis is freely rotated by pushingthe input axis in an axial direction.
 13. An endoscope apparatusaccording to claim 1, wherein the plurality of second operating membersprovided at the back surface of the operating unit are switches foroutputting a signal to freeze an endoscope image displayed on thedisplay means by pushing an input axis in an axial direction.
 14. Anendoscope apparatus according to claim 1, wherein the plurality ofsecond operating members are provided at the back surface of theoperating unit are switches for outputting a signal to control amagnification of an endoscope image displayed on the display means inaccordance with an inclined direction of an input axis when the inputaxis is freely rotated.
 15. An endoscope apparatus according to claim 1,wherein the plurality of second operating members provided at the backsurface of the operating unit are switches capable of selectivelyoperating an operation for freezing an endoscope image displayed on thedisplay means by pushing an input axis in an axial direction or anoperation for controlling a magnification of the endoscope imagedisplayed on the display means in accordance with an inclined directionof the input axis when the input axis is freely rotated.
 16. Anendoscope apparatus according to claim 1, wherein at least one of theplurality of first operating members provided at the front surface ofthe operating unit is an analog joystick for varying an output signal inaccordance with a slant angle of an operational shaft.
 17. An endoscopeapparatus according to claim 16, wherein the analog joystick includes aswitch for generating a signal by being connected to the operationalshaft to push the operational shaft in an axial direction.
 18. Anendoscope apparatus according to claim 17, wherein the analog joystickincludes a switch which is interlocked to pushing operation of theoperational shaft so that a bent shape of the bending portion can befixed or fixing can be released.
 19. An endoscope apparatus comprising:an insertion portion having image pickup means and a bending portionprovided at the distal end of the insertion portion; a bending drivedevice having a drive source for bending the bending portion; displaymeans for displaying an image picked up by the image pickup means; anoperating unit for remotely controlling the bending portion; and aplurality of operating members located on the back surface of theoperating unit such that they are within an operable range of aforefinger of a hand when grasping said operating unit.